Semiconductor device and method for tuning holding voltages in silicon controlled rectifier

A semiconductor device (900A) comprising:

• a substrate (914);
• a deeply diffused first region (910) and a deeply diffused second region (912) disposed and configured to form a p-n junction side by side in the substrate (914);
• first P+ implanted and diffused regions (904-1, 908-1) and first N+ implanted and diffused regions (902-1, 906-1) that are formed in both the deeply diffused first region (910) and the deeply diffused second region (912) and isolated by a shallow trench isolation (STI) (916);
• and
• second P+ implanted and diffused regions (902-2, 906-2) and second N+ implanted and diffused regions (904-2, 908-2) that are formed in both the deeply diffused first region (910) and the deeply diffused second region (912) and isolated by the STI (916),
• wherein the first P+ implanted and diffused regions (904-1, 908-1) over the second N+ implanted and diffused regions (904-2, 908-2) form the p-n junction, and wherein the first P+ implanted and diffused regions (904-1, 908-1) are configured to provide an electrical contact to an external environment, and the second P+ implanted and diffused regions (902-2, 906-2) are in direct contact with the deeply diffused first and second regions (910, 912);
• and
• wherein the first N+ implanted and diffused regions (902-1, 906-1) over the second P+ implanted and diffused regions (902-2, 906-2) form the p-n junction, and wherein the first N+ implanted and diffused regions (902-1, 906-1) are configured to provide an electrical contact to the external environment, and the second N+ implanted and diffused regions (904-2, 908-2) are in direct contact with the deeply diffused first and second regions (910, 912).